Katalina Jimenez was cold. So cold that her fingers were sluggish. So cold that she couldn’t stop crying.

Until now, her strategy for hiking the Pacific Crest Trail had been simple and effective: use minimal gear and move fast. On this day—June 3, 2009—her pack weighed less than 20 pounds, and she’d swapped her hiking shoes for sandals and socks. It had taken her only 38 days to pass through the scorching Southern California desert. Jimenez was making great time as she began ascending midsize Sierra peaks inside Sequoia National Park, starting with 2,600-foot Sharknose Ridge, about 15 miles south of Mount Whitney.

Jimenez, 36, had made one slight departure from fleet-footed efficiency: she was carrying a small orange emergency-messaging device, made by a company called Spot, that her mother had insisted she take. Though the satellite-linked unit allowed only one-way communication—she used it to trigger a daily e-mail that told family and friends in Minne sota that she was OK—it could save her life if the trip turned dangerous. A Help button would tell her contacts that she was in trouble, while a 911 button would issue a rescue alert in case of life-threatening emergency.

The morning had been perfect, with yellow sun filtering through dense evergreens. By noon clouds had moved in, the temperature had dropped, and there were snow flurries, so Jimenez decided to set up camp and let the front pass by. Her map showed a small pond and a clearing just off the trail, but by the time she reached it the area was blanketed with snow, and she couldn’t tell where the dirt ended and the water began. Her feet splooshed into the cold lake, soaking her socks and sending shivers up her legs.

Jimenez was still shaking when she found a dry patch to set up her tarp and mat. She climbed into her sleeping bag. Wet and alone, she pressed the Spot’s OK button and watched an LED light acknowledge that the message had been sent. It was still only 20 degrees out—not cold enough to put her in any real danger.

Three hours later, the weight of new snow was making the tarp sag and her mind race. This is how people die in the wilderness, Jimenez thought. You get cold and wet, and then you can’t warm up. Then it’s over. She conjured an image of a hiker coming down the trail and discovering her frozen body.

By 3:30, the loneliness and anxiety were overwhelming. She pressed Help. Then she fumbled with her compact camera and recorded a three-minute video, sobbing as she described her predicament. A few minutes later, she pressed 911—an act she would regret later, after the weather eased up and she walked to safety under her own steam.

At the time, though, rescuers knew only one thing: somebody was in trouble. Later that day, a California search-and-rescue heli copter was slicing through the sky.

WHEN IT WAS INTRODUCED in 1982, the U.S. emergency-beacon system relied on milk-jug-size transmitters aboard ships or aircraft that sent out automatic distress signals if they were submerged in salt water or came loose from mounting brackets in the event of a crash. The system was used almost exclusively to track distress calls from crippled boats and downed planes, situations in which the calamities were, almost by definition, life-threatening. Beacons immediately proved effective, cutting search-and-rescue times to a fraction of what they’d been before.

These days, beacons are a popular, affordable consumer item—you can buy a Spot device for $150 or a personal locator beacon (PLB) for $350—joining handheld GPS units on the must-have lists of hundreds of thousands of backpackers, hikers, skiers, kayakers, and sailors. The devices have been instrumental in saving hundreds of lives since they hit the market in 2002. As Katalina Jimenez’s example shows, however, there’s wide potential for errors of judgment and even misuse.

Though Jimenez wasn’t in grave danger, she believed she was, and her decision was one that many others might have made. But as search-and-rescue (SAR) pros are quick to point out, people often push the panic button in less dire circumstances. Matt Scharper, the 48-year-old deputy chief of the California Emergency Management Agency, says that not long ­after Spot devices were introduced in 2007, he started noticing that SAR teams were spending a lot of time responding to false alarms. He began collecting data from the 58 counties and three national parks within his purview and found that, out of a sample of 77 distress calls ­involving beacons from June 2007 to April 2011, 48 percent had no merit at all. They happened because somebody panicked, didn’t follow the device’s directions, or decided that a minor discomfort warranted a major emergency response.

Unfortunately, whether the motive is good, bad, or ridi culous, state-funded SAR teams are required to deploy when the buttons get pushed, and that can mean a considerable waste of time and money. “We have to react like it’s an emergency unless proven otherwise,” says Scharper, sounding exasperated. Beacons, he maintains, have become “yuppie 911.”

Scharper and other rescue pros offer telling anecdotes. Last winter, Scharper helped coordinate a search in which a sheriff was sent hiking up a slippery mountainside during a thunderstorm in response to a Spot call coming from somewhere in San Bernardino County. He found a man who was dry and warm inside a tent; he’d called for help mainly because he was worried about getting home late. Recently, a ranger at Grand Canyon National Park set out on an 18-mile midnight hike in search of a couple who’d beaconed for help. When the ranger arrived at their campsite, the woman who’d set off the Spot said she was worried because her companion was snoring so loudly that she thought he might need medical help. There’s also the infamous example of a 2009 outing on the Grand Canyon’s Royal Arch Loop whose members called for rescue three times because they decided the water in their bottles tasted just a bit too salty.

The list goes on. By Scharper’s estimate, unnecessary alarms have cost California search-and-rescue agencies several hundred thousand dollars over the past ten years. “Eventually,” he says, “the budget crisis is going to make us consider legislation to fine people who set off rescue missions without good cause.” To him, it’s an open question whether the liability should also extend to the companies that make the devices.

IF LEGISLATION and fines do come under consideration, it would help to have comprehensive information about the use and abuse of beacons. For instance, would penalties for false alarms make people in real danger opt against calling for help? Or would penalties simply streamline an overburdened system? Data that could answer these questions simply doesn’t exist, because there’s no single entity, public or private, responsible for keeping track of the devices.

Currently, there are two basic beacon types on the market. First introduced in 2002, PLBs—which are now produced by various private companies—are smaller versions of the beacons used on ships and aircraft. When activated, a PLB emits a radio signal every few minutes that emergency crews can track from the air or that the National Oceanic and Atmospheric Administration (NOAA), a federal agency, can triangulate using satellite data. Relying on this information, rescue teams home in on the source.

First sold in 2007 and manufactured by Louisiana-based Spot, a subsidiary of the satellite company Globalstar, a Spot device doesn’t give off a homing signal. Instead it calculates its own position and sends the coordinates and a short emergency message over the same network used by sat phones. The alerts are fielded by a private emergency-response center in Houston, which, in turn, notifies the appropriate local law-enforcement agency about the location of the signal.

The various kinds of Spot devices—there are five on the market now, ranging widely in sophistication—aren’t complicated to use, but several things can go wrong. A poorly packed unit can go off by itself if the buttons get mashed accidentally. As frequently happens, a Spot owner can fail to read the instructions, a lengthy manual that explains how and when to use the device.

Even experienced veterans aren’t immune to mistakes. In 2008, Steve Howe, an editor at Backpacker who was making his third attempt to climb 20,320-foot Denali, took along an early version of the Spot device. At one point well into his expedition, the Spot sent out a preset e-mail to his emergency contacts: “Steve Howe is injured or immobilized & cannot proceed, but has no immediate life-threatening condition. Evac please.”

For three hours, Howe’s colleagues at Backpacker frantically tried to find out more and get word to other climbers on the mountain. A ranger eventually located Howe at around 14,000 feet, coming down from a successful summit climb. He was fine. Somehow, the device had activated itself in his bag, probably by being pressed against other gear or from the pressure of him leaning on the pack. The event was widely reported on blogs, prompting Spot to alter the design to include a safety cap over the Help and 911 buttons.

According to NOAA, its network handles about 7,500 emergency distress calls every year, coming from a universe of roughly 75,000 registered PLBs. Of those, NOAA reported in 2010, almost 68 percent were later determined to be false alarms. The agency predicts that within five years, the number of PLB devices will increase sixfold, to 500,000.

Spot doesn’t keep comprehensive statis tics on how its beacons have been used, but company spokesman Derek Moore estimates that there are approximately 250,000 units in the field around the world, a number that could quadruple in the next five years. In 2010, distress calls from Spot devices initi ated roughly 500 rescue responses, but it’s unknown how many of those were false alarms. Despite the number of man-hours spent on each rescue, no government agency has conducted a study on the worthiness of distress calls, and Spot doesn’t have that information, other than to say there are “very few incidents.”

According to Moore, who works out of Spot’s offices in Milpitas, California, “The majority of incidents customers have used SOS for are things like broken bones and hypo thermia. Of course, as with any technology, there are some people who use it as a panic button when they could have gotten out on their own.” Moore adds that the company checks in every way that it can before initiating a formal rescue call: “We take [false alarms] very seriously.”

LIEUTENANT COLONEL Robert Russell—a rescue expert based at Tyndall Air Force Base in Florida, home to a national control center that works in conjunction with NOAA for land-based searches—is often the first person to receive a distress call from a PLB or a downed aircraft, and he agrees with Scharper that there’s a problem. Last year his team handled 3,288 beacon alerts, and he estimates that 63 percent of them were unnecessary. Russell worries that the rise in false alarms could make some SAR teams lose motivation.

“At some point, it becomes about human nature,” he says. “Every team is dedicated to what they do, but if they respond to four false alarms in a row, that will stick in their mind on the fifth mission. It could very well impact their support.”

Indeed, SAR teams are often staffed by volunteers, and missions require a certain amount of faith that the system isn’t being abused. One volunteer in Oregon told me he’d stopped responding to beacon alerts in 2009 after hiking 17 miles into the wilderness to find a man who had a leg cramp—a cramp that had vanished by the time the rescue crew arrived.

Of course, nuisances and headaches don’t change the fact that beacons do save lives. Steve Howe is pleased with the progress that equipment designers have made in rooting out glitches like the one he experienced, and he believes the devices solve more problems than they create. “I think the OK signals prevent far more unneeded call-outs from worried spouses, parents, and relatives than beacons create through false alerts,” he says. When problems do occur, it’s usually the person—not the device—that should get the blame. “The problem isn’t whether beacons should be part of the wilderness experience,” he says. “It’s whether some people should be allowed out of their yard.”

Greg Johnson, a commercial-fishing examiner in Charleston, South Carolina, who works closely with the Coast Guard when ocean beacons go off, has collected beacon data going back decades. He thinks the line between good and bad calls is difficult to discern, and he’d hate to see too much caution. While some searches may be unnecessary, he says, they’re a lot easier to conduct now than in the pre-beacon days, when teams had to comb hundreds of miles of ocean or wilderness with nothing to guide them. “Beacons save man-hours,” Johnson says. “Period.”

At least most of the time they do. In December 2009, Colorado SAR teams received the first of nine distress calls from a single unregistered beacon in use somewhere in the defunct ski resort Berthoud Pass, indicating that it was in the hands of a backcountry skier. The alerts kept coming for three months—intermittent PLB signals that would last 30 or 40 minutes at a time before going silent. The beacon had never been registered, so officials had no way of contacting the owner.

Paul “Woody” Woodward, a 52-year-old Alpine Rescue Team leader who’s one of nine SAR coordinators in Colorado, says he called in extra tracking equipment and helped organize a dragnet of police and rescue workers to find the rogue beacon. His crew hung posters with pictures of the beacon type on popular backcountry ski trails, just in case someone saw it dangling off the outside of a pack.

Woodward caught a break one day in February 2010 when the skier causing the problem forgot to turn off the beacon after his last run. Woodward was able to track the device to the parking lot of a doctor’s office, where he found the unwitting scofflaw.

“There were about six people who looked like scientists there, with all this high-tech gear pointing at my trunk,” says the errant skier, who spoke on condition of anonymity. “They knew exactly where I had been over the past three months and pinpointed every run.” The skier had gotten the PLB as a Christmas gift from his aunt, who told him it was an avalanche locator beacon that should be kept on every time he went out.

After giving the skier a healthy chewing-out, Woodward and his team made him sit down and register the beacon online. “I still carry it on the outside of my bag,” the skier says. “But I’m afraid to even touch it now.”

DESPITE THE SOPHISTICATION of the beacon Katalina Jimenez used, rescue coordinators somehow confused the GPS coordinates and began their search 20 miles from her position. Jimenez stayed inside her sleeping bag, tears in her eyes. She was cold but getting warmer every minute. Three hours after pressing 911, she canceled the alert. Then she took a Tylenol PM and went to sleep.

Park ranger George Durkee was one of at least a dozen people involved in the search for Jimenez, advising on the effort from his base in Sequoia and Kings Canyon National Park. He remembers being baffled by the logic behind the signals. “There was an OK message as well as several calls for emergency services, and we didn’t know what it meant,” he says. “Was she delirious and just mashing buttons, or was the situation somehow resolved?”

Katalina woke up in the early morning to a clear sky. “I could see the moon, and I knew that the storm was over,” she says. “It was still chilly, but I knew I would be able to walk out.”

She packed up and headed out, continuing on her route. By afternoon she’d arrived in the town of Lone Pine. There she made a pay-phone call to get in touch with her brother and tell him she was OK. As it happened, her brother was already in the same town, only a block away. He and her father had bought plane tickets the minute they received her first help alert.

“They had flown to Fresno and rented a car to help join the search for my body,” Jimenez says, the memory bringing up an overwhelming range of emotions. “Of course, they were elated that I was OK, but I had no idea that I would get this response from people for just pressing that button. I was cold, scared, and I panicked. It was more of a mental breakdown than a physical one.”

With a sixfold increase in the number of devices expected in the next five years, there will be many more opportunities for people to hit the panic button. Scharper says that, right now, there's at least one call a week, and some weeks there's a new call every day. It's a pattern he would like to reverse. "The bottom line," he says, "is that if you can save yourself, don't call search and rescue."

SCOTT CARNEY IS THE AUTHOR OF THE RED MARKET (WILLIAM MORROW), A NEW BOOK ABOUT THE GLOBAL TRAFFIC IN HUMAN BODY PARTS.

Bob asked, "Why aren't backpackers like this required to carry common sense?"

From the article:

When problems do occur, it’s usually the person—not the device—that should get the blame. “The problem isn’t whether beacons should be part of the wilderness experience,” he says. “It’s whether some people should be allowed out of their yard.”

People ask me why I carry a bigger/heavier/hotter/faster stove than what I really need. Hot drinks are about the quickest cure for hypothermia that I have ever found. I've been out in many a storm when "the other guy's stove wouldn't light" or some other such foolishness.

I even carry one Esbit tablet and a titanium sierra cup with me on a dayhike.

Or, what about requiring evacuation insurance in order to get a permit for backcountry camping? I pay it here in Spain (not mandatory to hike/camp, but required by the outdoors club I'm part of) and at about 70 euros for the year it makes sense to me...

the problem with charging (and possibly requiring insurance) ... is that people will go out anyways

this may make them less likely to press the shiny red button ... which while in some cases may be a good thing ... may also delay alerting SAR early enough to prevent a fatal situation

also its very possible or even likely that if SAR aint searching for em because no one pressed the big red button ... friends and family will go out and look for em anyways ... potentially causing more issues and rescues

ive said it before and ill say it again ... gear, whether it be too much of the heavy stuff, or just "enough" of the UL stuff, is absolutely no substitute for knowing what to do and keeping in the right frame of mind

i think too many people come to various intraweb sites and think "oh if i buy this and this and this gear, and it weights so much ... ill be totally fine and a backpacker"

you better know how to use that gear when the chips are down and have the ability to recognize when yr just panicking over a storm or when something dangerous is happening

i think its great that more and more people are enjoying the great outdoors ... i just dont think it wise that some are going into situations where they could be clueless as to what to do

personally id like to see much more discussion on here about basic common scenarios, rather than just gear, gear, gear ... but thats just my opinion

One of the many differences between SPOT and a PLB is that with the PLB you are notified up front when you register it that if it's not a life-and-death emergency and you push the button, the penalty is a hefty fine and/or a year or two free board and room in a federal prison.

For example, if my dog breaks a leg, I'm responsible for getting him out. If I push the button, I'd be in trouble. If I break a leg, though, I can legally push the button.

In some states, the rescuee gets to pay for the helicopter and/or horse time. Wyoming is one of those.